The proposed research is directed at attempts to isolate bioactive factors from demineralized adult bone. Such factors could be extremely useful in aspects of fracture repair or periodontal disease. We envision restoration of severe bone loss due to periodontal disease would be a major use for bioactive factors which originate from demineralized bone. Emphasis on this ultimate use stems from the ease and accessibility of tissue capable of responding to specific bioactive factors. The studies proposed here center on our efforts to purify three bioactivities: (1) the stimulation of the conversion of mesenchymal cells into chondrocytes; (2) the inhibition of mesenchymal cell development into chondrocytes and (3) mitotic and anti-mitotic activites. These three activities are associated with the in vivo response of demineralized bone matrix. Importantly, cell culture bioassays for these activities have been designed using stage 24 chick embryo limb bud mesenchymal cells. These cell cultures offer a reasonably fast, reproducible and reliable assay which is sensitive to Mug quantities of partially purified preparations from demineralized bone. The goals of this research are to pufify and characterize these bioactive factors and with the use of monoclonal antibodies, determine the cytological localization, site of synthesis and species cross-reactivity of these factors. Ultimately, we would like to delineate their mechanis(s) of action and to design delivery systems for their precise delivery to in vivo sites especially as related to periodontal disease.